Heater



FIG. 1 is a front, top and right side perspective view of a heatershowing our new design;

FIG. 2 is a back, top and left side perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a back elevational view thereof;

FIG. 5 is a right elevational side view thereof;

FIG. 6 is a left elevational side view thereof; and,

FIG. 7 is a top view thereof.

The ornamental design for a heater, as shown and described.